diff options
Diffstat (limited to 'activerecord/lib/active_record/attribute_methods.rb')
-rw-r--r-- | activerecord/lib/active_record/attribute_methods.rb | 62 |
1 files changed, 47 insertions, 15 deletions
diff --git a/activerecord/lib/active_record/attribute_methods.rb b/activerecord/lib/active_record/attribute_methods.rb index f4a4e3f605..9d58a19304 100644 --- a/activerecord/lib/active_record/attribute_methods.rb +++ b/activerecord/lib/active_record/attribute_methods.rb @@ -1,4 +1,5 @@ require 'active_support/core_ext/enumerable' +require 'active_support/core_ext/string/filters' require 'mutex_m' require 'thread_safe' @@ -82,7 +83,7 @@ module ActiveRecord generated_attribute_methods.synchronize do return false if @attribute_methods_generated superclass.define_attribute_methods unless self == base_class - super(column_names) + super(attribute_names) @attribute_methods_generated = true end true @@ -90,7 +91,7 @@ module ActiveRecord def undefine_attribute_methods # :nodoc: generated_attribute_methods.synchronize do - super if @attribute_methods_generated + super if defined?(@attribute_methods_generated) && @attribute_methods_generated @attribute_methods_generated = false end end @@ -149,7 +150,7 @@ module ActiveRecord BLACKLISTED_CLASS_METHODS.include?(method_name.to_s) || class_method_defined_within?(method_name, Base) end - def class_method_defined_within?(name, klass, superklass = klass.superclass) # :nodoc + def class_method_defined_within?(name, klass, superklass = klass.superclass) # :nodoc: if klass.respond_to?(name, true) if superklass.respond_to?(name, true) klass.method(name).owner != superklass.method(name).owner @@ -184,14 +185,15 @@ module ActiveRecord # # => ["id", "created_at", "updated_at", "name", "age"] def attribute_names @attribute_names ||= if !abstract_class? && table_exists? - column_names + attribute_types.keys else [] end end # Returns the column object for the named attribute. - # Returns nil if the named attribute does not exist. + # Returns a +ActiveRecord::ConnectionAdapters::NullColumn+ if the + # named attribute does not exist. # # class Person < ActiveRecord::Base # end @@ -201,21 +203,18 @@ module ActiveRecord # # => #<ActiveRecord::ConnectionAdapters::Column:0x007ff4ab083980 @name="name", @sql_type="varchar(255)", @null=true, ...> # # person.column_for_attribute(:nothing) - # # => nil + # # => #<ActiveRecord::ConnectionAdapters::NullColumn:0xXXX @name=nil, @sql_type=nil, @cast_type=#<Type::Value>, ...> def column_for_attribute(name) - column = columns_hash[name.to_s] - if column.nil? - ActiveSupport::Deprecation.warn \ - "`column_for_attribute` will return a null object for non-existent columns " \ - "in Rails 5.0. Use `has_attribute?` if you need to check for an attribute's existence." + name = name.to_s + columns_hash.fetch(name) do + ConnectionAdapters::NullColumn.new(name) end - column end end # A Person object with a name attribute can ask <tt>person.respond_to?(:name)</tt>, # <tt>person.respond_to?(:name=)</tt>, and <tt>person.respond_to?(:name?)</tt> - # which will all return +true+. It also define the attribute methods if they have + # which will all return +true+. It also defines the attribute methods if they have # not been generated. # # class Person < ActiveRecord::Base @@ -329,7 +328,7 @@ module ActiveRecord # task.attribute_present?(:title) # => true # task.attribute_present?(:is_done) # => true def attribute_present?(attribute) - value = read_attribute(attribute) + value = _read_attribute(attribute) !value.nil? && !(value.respond_to?(:empty?) && value.empty?) end @@ -370,6 +369,39 @@ module ActiveRecord write_attribute(attr_name, value) end + # Returns the name of all database fields which have been read from this + # model. This can be useful in development mode to determine which fields + # need to be selected. For performance critical pages, selecting only the + # required fields can be an easy performance win (assuming you aren't using + # all of the fields on the model). + # + # For example: + # + # class PostsController < ActionController::Base + # after_action :print_accessed_fields, only: :index + # + # def index + # @posts = Post.all + # end + # + # private + # + # def print_accessed_fields + # p @posts.first.accessed_fields + # end + # end + # + # Which allows you to quickly change your code to: + # + # class PostsController < ActionController::Base + # def index + # @posts = Post.select(:id, :title, :author_id, :updated_at) + # end + # end + def accessed_fields + @attributes.accessed + end + protected def clone_attribute_value(reader_method, attribute_name) # :nodoc: @@ -430,7 +462,7 @@ module ActiveRecord end def typecasted_attribute_value(name) - read_attribute(name) + _read_attribute(name) end end end |